I have Adc 2 connected to an existing 2.5bar Bosch MAP sensor. I want the display to only show boost not vac. The values I have inputted are 0.3v at -0.8bar and 4.65v at +1.5bar. These were obtained from the Bosch data sheet. The UTCOMP calculator gave a= 0.53 and b= -0.96. With the engine off, the display shows 0 psi as it should, but with the engine running the display shows 7 or 8 psi . The engine creates no boost at idle and my ECU which is using the same MAP sensor is showing 48kpa (absolute), so why is the UTCOMP showing this boost pressure?. Am I using the correct figures ?
Thanks